"It is one thing to lug technologies around, another thing to wear them, and even more intrusive to bear them... But that's the direction in which we're headed."

"I think we're entering an era of person-view systems which will show things on ground level and will be increasingly relayed to others via social media.

"We've got people wearing recording devices on their fingers, in their caps or sunglasses - there are huge legal and ethical implications here."